Re^2: Perl/Tk and exit(0) [Tk::exit]

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Re^3: Perl/Tk and exit(0) [Tk::exit] by 1nickt (Canon) on Apr 03, 2020 at 07:43 UTC
Thanks Ken, I'll update the link. Not sure how that happened. Update: I fixed the links by changing from `[perldoc://` to `[doc://`. I wonder if the behaviour of the former syntax is new, broken, or something I just imagined was different. The links as I originally posted definitely went to a Goog search. Maybe a topic for PM Discussion... The way forward always starts with a minimal test.	[reply] [d/l] [select]
Re^4: Perl/Tk and exit(0) [Tk::exit] by kcott (Archbishop) on Apr 03, 2020 at 08:33 UTC
"I wonder if the behaviour of the former syntax is new, broken, or something I just imagined was different." Unfortunately, I suspect it may be the latter. I rarely, if ever, use those shortcuts; however, checking in "What shortcuts can I use for linking to other information?", I see (my emphasis added): The Perl documentation: Search the Perl docs: `[perldoc://search terms]` Link directly to a the doc of a function or variable: `[doc://name]` ... There was a change to `[doc://name]` back in February: "NEW [doc://perldoc#deeplink] works now with all perldocs". I don't recall any recent changes to `[perldoc://search terms]`. "Maybe a topic for PM Discussion..." Or maybe not. :-) Unless you wish to request a typo fix: `s/to a the doc/to the doc/` — Ken	[reply] [d/l] [select]
Re^5: Perl/Tk and exit(0) [Tk::exit] by choroba (Cardinal) on Apr 03, 2020 at 13:11 UTC
`[perldoc://search term]` links to a Google search for the term in perldoc. It doesn't have another choice, in fact, as the current version of perldoc.perl.org (unlike the perldoc.pl) doesn't have a working search. BTW, note the "official" documentation still shows 5.30.0, while the "open" documentation site correctly shows the latest 5.30.2. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]
Re^3: Perl/Tk and exit(0) [Tk::exit] by jcb (Parson) on Apr 03, 2020 at 23:54 UTC
As I understand, the two `exit` procedures only matter if you fork. Calling Tk's `exit` from a forked child causes the parent to also exit, while calling `CORE::exit` causes only that forked child to exit.	[reply] [d/l] [select]
Re^4: Perl/Tk and exit(0) [Tk::exit] by kcott (Archbishop) on Apr 04, 2020 at 06:59 UTC
G'day jcb, I'm unsure whether you posted this to corroborate what I said or correct something you believed I had wrong in some way. So, purely by way of clarification: I was pointing out that the `exit` in a Tk script was the one described in https://metacpan.org/pod/distribution/Tk/pod/exit.pod and not the one described in https://perldoc.perl.org/functions/exit.html. I was not, in any way, suggesting that changing from `Tk::exit` to `CORE::exit` would be beneficial for the OP. In fact, I wrote: "Knowing that doesn't help the OP ...". What you wrote ("As I understand, the two `exit` procedures ...") pretty much paraphrases what's in the Tk::exit documentation; i.e. "Using `exit` from a forked process will terminate both the child process and* the parent process. As `Tk::exit` is imported by default one should use `CORE::exit` in the forked process instead.". The reason to generally prefer `Tk::exit` over `CORE::exit` is given in the preceding paragraph: "If calling `exit` from code invoked via a Tk callback then this Tk version of `exit` cleans up more reliably than using the perl `exit`."*. If there was any miscommunication or misunderstanding, I hope that clears it up. — Ken	[reply] [d/l] [select]
Re^5: Perl/Tk and exit(0) [Tk::exit] by jcb (Parson) on Apr 04, 2020 at 23:33 UTC
It was intended to corroborate and to point out a difference that helps to explain why Tk replaces `exit`. My understanding of the two is from the documentation and my experience, which does not include Tk on Windows, so the difference I know about is that `Tk::exit` reliably destroys all of the MainWindows, while `CORE::exit` allows a forked worker (such as performing an LWP request without blocking the GUI) to safely exit after reporting its results back. On X11, calling `Tk::exit` from a forked child also causes the parent to exit.	[reply] [d/l] [select]
Re^6: Perl/Tk and exit(0) [Tk::exit] by kcott (Archbishop) on Apr 05, 2020 at 00:26 UTC
Re^4: Perl/Tk and exit(0) [Tk::exit] by Anonymous Monk on Apr 04, 2020 at 04:41 UTC
As I understand, the two exit procedures only matter if you fork. This is on windows, clean exit `perl -e"use Tk; $mw=tkinit; $mw->Button(-command=>sub{ Tk::exit })->pa +ck; MainLoop; "` [download] Dirty exit `perl -e"use Tk; $mw=tkinit; $mw->Button(-command=>sub{ CORE::exit })-> +pack; MainLoop; " perl.exe has encountered a problem and needs to close. Faulting application perl.exe, version 5.20.3.3, faulting module tk.xs +.dll, version 8.4.2.5, fault address 0x00044b1e.` [download]	[reply] [d/l] [select]


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